Roof-framing square.



H. H. CRISS. ROOF FRAMING SQUARE. APPLIoATIoN FILED SEPT. ao, 1910.

Patented Oct. 31, 1911.

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HUDSON H. CRISS, OF GLOBE, ARIZONA TERRITORY.

ROOF-FRAMING- SQUARE.

Specification of Letters Patent.

Patented oet. 31, 1911.

Application filed September 30, 1910. Serial No. 584,685.

To all whom 'it may concern: I

Be it known that I, I-IUDsoN I-I. CRIss, a citizen of the United States,and a resident of Globe, county of Gila, and Territory of Arizona, haveinvented certain new and useful Improvements in Roof-Framing Squares, ofwhich the vfollowing is a specification.

My invention is an improvement in roof framing squares, and consists incertain novel constructions and combinations of parts, hereinafterdescribed and claimed.

The object of the invention is to provide a simple device of thecharacter specified, by means of which rafters of all kinds may be laid0E with absolute correctness, and without the necessity of anycalculation upon the part of the user.

Referring to the drawings forming a part hereof, Figure 1 is aperspective view of the improvement folded. Fig. 2 is a similar viewpartly unfolded. Fig. 3 is an enlarged partial plan view. Fig. 4 is atransverse section near one end. Fig. 5 is an enlarged detail plan viewof one end looking at the opposite side from Fig. 3, and, Fig. 6 is atransverse section on the line of the pivotal connection of the bladeand handle.

In the present embodiment of the invention, a handle A is provided, towhich are pivoted three blades B, C, and D. The handle A is angular incross section, consisting of two sides 1 and 2, meeting atone edge at aright angle, and at each end the handle is slotted as shown at 3, at thejunction of the two sides, the inner ends of the slots being beveled asshown at 4. The side 1 of the handle is enlarged or thickened at eachend on its outer face as at 7, and the side 2 is enlarged or thickenedat one end on its outer face as shown at 7a. The blades B, C and D arepivotally connected to the handle in the same manner, so that theconnection of but one blade will be described, the construction beingthe same for each blade.

Each of the blades is connected to the handle by means of a threadedstem 5 formed or secured on the blade extending laterally, and passingthrough an opening in the-handle. Each blade is provided with anenlargement 16 circular in cross section, and concentric with the stem,and the enlargement is received in a circular opening 13 in the handleside. The opening 13 has the edge remote from the blade beveledoutwardly as shown at 13aL in Fig. 6, and a disk 14 having undercut sidewalls is itted in the end of the opening and abuts against the face ofthe circular enlargement. Dowel pins 15 are arranged in thedisk andenlargement to constrain the disk to move with the blade, and the diskis provided with a central opening through which passes the threadedstem. A thumb nut 6 engages the stem on the outer side of the disk andholds the blade and disk together. The beveled end of the opening andthe undercut wall of the disk prevent movement of the blade away fromthe handle, and the disk will rotate with the blade. The disk isprovided with an indicator 17a, and the handle is provided with anarc-shaped scale 17 arranged alongside the disk and coperating with theindicator. The scale indicates the angle of the blade with the handleand by loosening the nut 6, either of the blades may be moved withrespect to the handle, and when in proper 'position the tightening ofthe thumb nut will hold the blade in adjusted position.

rIhe outer corners of the4 side 1 of the handle are rounded as shown at8, and one corner of each blade is rounded-as shown at 9. The othercorner of each blade is provided with a longitudinally extendingtriangular lug 10, which moves into the slot 3, and limits the openingmovement of the blade, holding the said blade at right angles to thehandle.

It will be understood that the blades B and C are pivoted to theopposite ends of the handle side 1, while the blade D is pivoted to oneend of the handle side 2, adjacent to the blade C. The blades B 'and Care provided with scales or tables 12 and 19, one on the face of eachblade, and the said tables will later be described fully. The free endsof the blades B and C are beveled in the same direction as shown at 11and the lblades are of such length that when folded on the handle side,the end of the blade B abuts the end of the blade C, as indicated inFig. 1. The inner face of the handle side 2 is thickened on its innerface at 18, at the end remote from the blade D, so that the inner faceof the thickened portion is flush with the inner face of the blade. 'Ihefree end of the blade D is also beveled as shown at 20, and when foldedthe square is compact, easy to handle, and of light weight. The bladesmay take any position with ,respect to the handle from 0o to 90o inaccordance with the pitch of the roof, and the indicator 17a will showthe out for the rafters on the scale 17.

As is known, the jack rafters are the short rafters running from theplate or base to the hip rafters, or from the valley rafters to theridge, and each pair is shorter than the proceeding pair, thedifferences in length depending upon the pitch of the roof, andaccording to the distance of the rafters from each other. For instancewith a pitch of eight inches to the foot and a spacing of twenty-fourinches, each pair of such rafters is 28.84 inches shorter than `theproceeding pair.

The table 19 is designed to give the length of the ack rafters. Forinstance if the rise per foot of the roof is three inches, and the jackrafters are spaced twelve inches apart, each pair of jack rafters willbe 12.37 inches shorter than the preceding pair. The table is arrangedfor the most common spacing and the most common pitch of roof, thelatter running from three inches per foot to twelve inches per foot, andthe former from twelve inches spacing to thirty-six inches.

The table 12 is designed to give the length of common or hip and valleyrafters, and the length is obtained by multiplying the number under therise in inches per foot by half the width of the building. For instance,in a building twenty-four feet in width, the number 1.56 is found underthe rise in inches per foot for hip and valley rafters. This numbermultiplied by l2 gives 18.72 feet. For common rafters the number 1.20 isfound and by a similar process the result of 14.4 feet is obtained.

The scales 17 are used as follows. Each scale 21-22 is composed ofgraduations numbered from 3 to l2. The inner scale 2l is made use of'toobtain the level of the common and jack rafters, and the outer scale 22to obtain the level of the hip and valley rafters. It is only necessaryto adjust the blade until the indicator 17a registers with the numeraldesignating the rise in inches per foot of the roof, and the angle ofthe blades is the angle of the rafter.

I claim:

l. In a device of the character specified, a handle composed of an angleplate having its two sides arranged at right angles to each other, ablade hinged at each end of one of the sides, and of a length to abut attheir ends when folded on said side, said ends being beveled in oppositedirections and fitting each other, a blade hinged to one end of theother side, each of said blades having an angular lug extending beyondthe side at its end, the handle being slotted lto receive the said lugwhen the blades are at right angles to the handle to limit the openingmovement of the blades to such position.

2. In a device of the character specified, a handle having at one end acircular opening, said opening flaring toward one face of the handle, ablade having an enlargement on one face near one end fitting within theopening, and on the opposite side of the handle from the fiaring end ofthe opening, a disk fitting within the flaring end of the opening andabutting against the face of the enlargement, dowel pins connecting thedisk and the blade, means for clamping the disk and blade together, thehandle having a scale adjacent to the disk and the disk having anindicator coperating therewith, said blade having a lug extending on theoppo site of the handle from the blade, the handle having a stop forengagement by the lug to limit the opening movement of the blade to aposition at right angles with the handle.

3. In a device of the character specified, a handle having at one end acircular opening, said opening fiaring toward one face of the handle, ablade having an enlargement on one face near one end fitting within theopening, and on the opposite side of the handle from the flaring end ofthe opening, a disk fitting Within the flaring end of the opening andabutting against the face of the enlargement, dowel pins connectingthedisk and the blade, and means for clamping the disk and handle together.

HUDSON H. CRISS. Witnesses:

J. F. Barcos, HlMoN THOMAS.

Copies of this patent may be obtained for ve cents each, by addressingthe Commissioner of Patents, Washington, D. C.

